Grinding method for ferrite magnetic powder

Abstract

The invention provides a grinding method for ferrite magnetic powder. The grinding method comprises the following steps: weighing raw materials of the ferrite magnetic powder; carrying out size mixing on the ferrite magnetic powder with water, preparing the ferrite magnetic powder raw material into a size, and completely dispersing the size; grinding the slurry by using a vertical mill; after grinding is completed, the ground slurry is dried; dispersing and sieving the dried ferrite magnetic powder; and carrying out finished product packaging on the sieved ferrite magnetic powder. According to the grinding method, the vertical grinding machine is used, so that the effects of improving the fine grinding efficiency and the superfine grinding efficiency and reducing the energy consumption and the medium consumption are achieved; the total number of equipment used in the original process is reduced, and the production cost is reduced; continuous ore grinding can be achieved, and the automation degree is high; the technical problems that traditional ferrite magnetic powder superfine grinding is large in manual labor intensity, low in automation degree, large in energy consumption and prone to excessive grinding are solved, and the effects of improving fine grinding and superfine grinding efficiency and reducing energy consumption and medium consumption are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetic materials, and particularly to a grinding method for ferrite magnetic powder. Background Art

[0002] Ferrite magnetic powder is a magnetic material prepared by sintering a mixture of iron oxide and one or more other metal oxides (such as zinc oxide, manganese oxide, barium oxide, strontium oxide, etc.), and has excellent magnetic properties, including high magnetic permeability, low loss, and good magnetic stability.

[0003] In the existing production process of ferrite magnetic powder (as shown in Figure 1 ), the equipment in the grinding process section mainly uses traditional horizontal ball mills, which have problems such as high energy consumption, low efficiency; intermittent grinding in the production process, low automation level; high labor intensity of workers, low production efficiency; and too large proportions of fine-grained and coarse-grained products, resulting in high cost input in the entire production process and relatively low product added value, restricting the further expansion of the production capacity of the production base, and urgently needing to be solved.

[0004] In view of this, the present invention is particularly proposed. Summary of the Invention

[0005] The purpose of the present invention is to provide a grinding method for ferrite magnetic powder, which improves the efficiency of fine grinding and ultrafine grinding, and avoids the problems of easy over-grinding, high energy consumption, and high medium consumption in the traditional method.

[0006] In the first aspect of the present invention, a grinding method for ferrite magnetic powder is provided, including the following steps:

[0007] S1. Weigh the raw materials of the ferrite magnetic powder;

[0008] S2. Adjust the slurry of the ferrite magnetic powder with water to make the raw material of the ferrite magnetic powder into a slurry and fully disperse it;

[0009] S3. Grind the slurry with a vertical mill;

[0010] S4. After grinding, dry the ground slurry;

[0011] S5. Disperse and screen the dried ferrite magnetic powder;

[0012] S6. Package the screened ferrite magnetic powder into finished products.

[0013] Preferably, in step S2, the concentration of the slurry made from the raw material of the ferrite magnetic powder is controlled at 5% - 50%; more preferably, the concentration of the slurry made from the raw material of the ferrite magnetic powder is controlled at 30% - 50%.

[0014] Preferably, in step S3, the stirrer of the vertical mill adopts any one of a rod-type stirrer or a disk-type stirrer.

[0015] Preferably, the peripheral linear velocity of the stirrer of the vertical mill is controlled at 8 m / s to 14 m / s.

[0016] Preferably, the Mohs hardness of the grinding medium in the vertical mill is 7 to 10.

[0017] Preferably, the density of the grinding medium is 3.6 to 4.6 g / cm.

[0018] Preferably, the diameter of the grinding medium is 2 mm to 5 mm; more preferably, the diameter of the grinding medium is 2 mm to 3 mm.

[0019] Preferably, the filling rate of the grinding medium is 30% to 70%; more preferably, the filling rate of the grinding medium is 50% to 70%.

[0020] Preferably, the grinding method for ferrite magnetic powder comprises the following steps:

[0021] S1. Weigh the raw material of ferrite magnetic powder using an industrial scale;

[0022] S2. Transport the ferrite magnetic powder to a stirring tank, add a certain amount of water in the stirring tank to slurry the ferrite magnetic powder, and make the raw material of ferrite magnetic powder into a slurry and fully disperse it;

[0023] S3. Start the vertical mill, and pump the slurry into the vertical mill for grinding;

[0024] S4. After grinding, pump the ground slurry into a drying device for drying;

[0025] S5. Pump the dried ferrite magnetic powder onto a sieve and then disperse it;

[0026] S6. Package the sieved ferrite magnetic powder into finished products through a packing machine.

[0027] In the second aspect of the present invention, there is provided a grinding system for ferrite magnetic powder, comprising an industrial scale, a stirring tank, a vertical mill, a drying device, a sieve and a packing machine which are connected in sequence.

[0028] Preferably, the stirrer of the vertical mill adopts any one of a rod-type stirrer or a disk-type stirrer. For the rod-type stirrer, the number of rods, the number of rod layers, and the rod shape can be selected according to actual needs without strict restrictions; for the disk-type stirrer, the number of disks, the number of disk layers, and the disk shape can be selected according to actual needs without strict restrictions.

[0029] The present invention has at least the following beneficial effects:

[0030] (1) The grinding method of the present invention uses a vertical mill, and a rod-type or disc-type agitator can be selected according to the particle size requirements. The peripheral line speed of the agitator, the diameter of the grinding medium, and the filling rate can be selected, thereby improving the effect of targeted fine and ultrafine grinding, and the grinding efficiency can be increased by more than 30%. Moreover, self-classification inside the vertical mill can prevent over-grinding, reduce power consumption, and save economic costs.

[0031] (2) The grinding method of the present invention realizes the ultrafine grinding of ferrite magnetic powder, shortens the original process, has low energy consumption and high efficiency, reduces the total number of equipment used in the original process, uses one less mill and one less industrial scale, and reduces production costs.

[0032] (3) The grinding method of the present invention can achieve continuous grinding and has a high degree of automation.

[0033] (4) The grinding method of the present invention solves the technical problems of the traditional ultrafine grinding of ferrite magnetic powder, such as high manual labor intensity, low degree of automation, high energy consumption, and easy over-grinding, and realizes the effects of improving the efficiency of fine and ultrafine grinding, reducing energy consumption and medium consumption. Description of the Drawings

[0034] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0035] Figure 1 It is a schematic flow chart of the grinding method for ferrite magnetic powder in the prior art.

[0036] Figure 2 It is a schematic flow chart of the grinding method for ferrite magnetic powder provided by the present invention.

[0037] Figure 3 It is a schematic diagram of the rod-type agitator of the vertical mill provided by the present invention.

[0038] Figure 4 It is a schematic diagram of the disc-type agitator of the vertical mill provided by the present invention. Detailed Embodiments

[0039] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0040] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular forms also include the plural forms. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they specify the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0041] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0042] Embodiment

[0043] As Figure 2 shown, this embodiment provides a grinding method for ferrite magnetic powder, including the following steps:

[0044] S1. Use an industrial scale to weigh the raw materials of the ferrite magnetic powder;

[0045] S2. Transport the ferrite magnetic powder to a stirring tank, add a certain amount of water to the stirring tank to adjust the slurry of the ferrite magnetic powder, and make the raw material of the ferrite magnetic powder into a slurry that meets the process requirements and is completely dispersed;

[0046] S3. Start the vertical mill, adjust it to the target rotational speed and linear speed. After the equipment runs stably, transport the pre-mixed and uniform slurry to the inside of the vertical mill through a slurry pump for grinding;

[0047] S4. After grinding, pump the ground slurry to a drying device to be completely dried;

[0048] S5. After completely drying the ferrite magnetic powder, pump it to a sieve and disperse it to prevent the ferrite magnetic powder from caking;

[0049] S6. Package the sieved ferrite magnetic powder into finished products through a packing machine.

[0050] In this embodiment, according to the requirements of different ferrite magnetic powders, determine the type of agitator (disk type, rod type, etc.), rotational speed, filling rate of grinding medium, slurry concentration, feed particle size, and product particle size of the vertical mill.

[0051] In this embodiment, according to the grinding requirements, the concentration of the slurry made from the ferrite magnetic powder raw material by using devices such as a stirring tank is controlled at 30% - 50%. At this concentration, the physical properties of the solid-liquid two-phase can be balanced, avoiding particle sedimentation due to too low solid content in the low-concentration slurry and preventing stratification or caking due to too high viscosity in the high-concentration slurry; moreover, the viscosity of the slurry is moderate at this concentration, which not only meets the requirements of pumping and pipeline transportation but also can maintain uniform dispersion in subsequent processes, reducing process fluctuations and being suitable for industrial continuous production; in addition, the interaction force between particles in the slurry is weakened at this concentration, and it is easier to optimize the particle size distribution through stirring and grinding.

[0052] In this embodiment, the peripheral speed of the stirrer of the vertical mill is controlled at 8 m / s - 14 m / s. The increase in the peripheral speed of the stirrer will increase the relative movement speed between the medium balls and the material, thereby enhancing the shear force and impact force and promoting the crushing and refinement of the material. Within this peripheral speed range, the stirrer can more effectively transfer energy to the grinding medium, causing the medium to form a stronger turbulent motion in the mill and improving the grinding efficiency. Too high a peripheral speed will lead to increased collisions between the medium balls, resulting in energy waste; while too low a peripheral speed cannot fully stimulate the grinding effect of the medium. This peripheral speed range can balance the two and reduce the loss of useless work. The peripheral speed directly affects the motion state and grinding intensity of the grinding medium, and thus affects the particle size distribution of the product. This peripheral speed range helps to achieve finer particle size control, improve product quality, and this peripheral speed also helps to maintain a reasonable medium filling rate and grinding concentration in the mill, avoiding a decrease in grinding efficiency caused by too high or too low a concentration.

[0053] In this embodiment, the required grinding medium is configured according to the requirements of ratio, density, and diameter and is pre-added to the inside of the cylinder of the vertical mill, and there is no restriction on the type of grinding medium.

[0054] In this embodiment, the Mohs hardness of the grinding medium is 7 - 10, which can effectively crush the ferrite magnetic powder, reduce the wear of the medium itself, and extend the service life.

[0055] In this embodiment, the density of the grinding medium is 3.6 - 4.6 g / cm³, and it has greater kinetic energy at the same peripheral speed, improving the grinding efficiency.

[0056] In this embodiment, the diameter of the grinding medium is 2 mm - 3 mm, which has a larger contact area with the material, grinds more evenly, reduces the phenomenon of over-grinding, and moves more violently in the mill, enhancing the shear force and promoting the refinement of the material.

[0057] In this embodiment, the filling rate of the grinding medium is 50% - 70%, avoiding an increase in energy consumption caused by too much grinding medium or insufficient grinding caused by too little grinding medium, balancing energy consumption and efficiency, and reducing the collision frequency between the media and energy waste.

[0058] This embodiment also provides a grinding system for ferrite magnetic powder, which includes an industrial scale, a stirring tank, a vertical mill, a drying device, a sieve, and a packing machine connected in sequence.

[0059] In this embodiment, the stirrer of the vertical mill adopts a rod-type stirrer (as shown in Figure 3 ), or a disk-type stirrer (as shown in Figure 4 ), and any one of them can be used; for the rod-type stirrer, the number of rods, the number of rod layers, and the rod shape can all be changed; for the disk-type stirrer, the number of disks, the number of disk layers, and the disk shape can all be changed, not limited to the forms shown in the figures.

[0060] The rod-type stirrer has a simple structure and is usually composed of multiple pin rods installed in a specific manner (such as the ordinary type, multi-layer type, and staggered type). The rod-type stirrer uses gravity and friction to achieve material refinement, has a moderate stirring power, and the total kinetic energy of the mixture is evenly distributed, which is suitable for processing medium-grained grinding. Its lower rotation speed and friction can reduce the temperature rise during the grinding process, reduce material adhesion, and maintain the magnetic properties of the magnetic powder.

[0061] The disk-type stirrer forms multiple grinding chambers through a high-speed rotating grinding disk, and realizes ultrafine grinding by using extremely high grinding and peeling force and energy density. The disk-type stirrer can achieve efficient refinement through high energy input and strong shear force, can significantly shorten the grinding time, and improve production efficiency.

[0062] In summary, through the use of a vertical mill in the grinding method of the present invention, a rod-type or disk-type stirrer can be selected according to the particle size requirements, and the peripheral linear velocity of the stirrer, the diameter of the grinding medium, and the filling rate can be selected, thereby improving the effect of targeted fine and ultrafine grinding, and the grinding efficiency can be increased by more than 30%; moreover, self-classification inside the vertical mill can prevent over-grinding, reduce power consumption, and save economic costs. The grinding method of the present invention realizes ultrafine grinding of ferrite magnetic powder, shortens the original process, has low energy consumption and high efficiency, reduces the total number of equipment used in the original process, uses one less mill and one less industrial scale, and reduces production costs. The grinding method of the present invention can achieve continuous grinding and has a high degree of automation. The grinding method of the present invention solves the technical problems of the traditional ultrafine grinding of ferrite magnetic powder, such as high manual labor intensity, low automation degree, high energy consumption, and easy over-grinding, and realizes the effects of improving the efficiency of fine grinding and ultrafine grinding, reducing energy consumption and medium consumption.

[0063] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A grinding method for ferrite magnetic powder, characterized in that: The steps include: S1. Weigh the raw materials of ferrite magnetic powder; S2, slurrying the ferrite magnetic powder with water, making the ferrite magnetic powder raw material into a slurry and completely dispersing it; S3, grinding the slurry using a vertical mill; S4, after the grinding is completed, the ground slurry is dried; S5, dispersing and sieving the dried ferrite magnetic powder; S6. Pack the sieved ferrite powder into finished products.

2. The grinding method for ferrite magnetic powder according to claim 1, characterized in that: In step S2, the concentration of the slurry made of the ferrite magnetic powder raw material is controlled at 5% to 50%.

3. The grinding method for ferrite magnetic powder according to claim 2, characterized in that: The concentration of the slurry made of the ferrite magnetic powder raw material is controlled at 30% to 50%.

4. The grinding method for ferrite magnetic powder according to claim 1, characterized in that: In step S3, the stirrer of the vertical mill is a rod stirrer or a disc stirrer.

5. The grinding method for ferrite magnetic powder according to claim 4, characterized in that: The edge linear speed of the stirrer of the vertical mill is controlled at 8m / s to 14m / s.

6. The grinding method for ferrite magnetic powder according to claim 1, characterized in that: The grinding medium in the vertical mill has a Mohs hardness of 7 to 10, a density of 3.6 to 4.6 g / cm, a diameter of 2 mm to 5 mm, and a filling rate of 30% to 70%.

7. The grinding method for ferrite magnetic powder according to claim 6, characterized in that: The diameter of the grinding medium is 2 mm to 3 mm, and the filling rate is 50% to 70%.

8. The grinding method for ferrite magnetic powder according to claim 1, characterized in that: The steps include: S1. Use an industrial scale to weigh the raw materials of ferrite magnetic powder; S2, conveying the ferrite magnetic powder to a stirring tank, adding a certain amount of water in the stirring tank to slurry the ferrite magnetic powder, making the ferrite magnetic powder raw material into a slurry and completely dispersing it; S3, starting the vertical mill, and grinding the slurry into the vertical mill; S4, after grinding is completed, the ground slurry is sent to a drying device for drying; S5, putting the dried ferrite magnetic powder onto a sieve for dispersion; S6. Use a baler to package the sieved ferrite powder into finished products.

9. A grinding system for ferrite magnetic powder, characterized in that: It consists of an industrial scale, a mixing tank, a vertical mill, a drying device, a sieve and a baler connected in sequence.

10. The grinding system for ferrite magnetic powder according to claim 9, characterized in that: The stirrer of the vertical mill is a rod stirrer or a disk stirrer.

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